When you factor, it becomes
(3x + 5) (x + 2)
You can do this by finding all factors of the coefficient in the first term, 3x^2.
So, the factors of 3 must be 3 and 1.
Then, find the factors of the 10 at the end, I used 5 and 2.
Now, just find a way to arrange the factors so they multiple correctly.
Hope this helps! :)